The present invention relates to cover systems for hauling vehicles, and particularly to extendible/retractable tarping systems for flatbed vehicles.
Retractable covers for load-carrying vehicles have been known for nearly a century. A folding wagon top was disclosed in U.S. Pat. No. 905,571 in which a flexible cover was folded forward across the load bed to provide easy access for loading and unloading goods from the bed. In U.S. Pat. No. 1,263,759, a retractable vehicle cover was disclosed in which the cover was supported on U-shaped bows that were slidably mounted on bars along opposite sides of the vehicle body. These concepts were adapted to a retractable cover for use on a flatbed tractor-trailer system in U.S. Pat. No. 3,326,598.
In spite of this long history, the extendable-retractable cover system did not achieve commercial viability and success until the CONESTOGA® tarping system was introduced by Aero Industries, Inc. in the late 1980's. Details of this tarping system are disclosed in U.S. Pat. Nos. 4,711,484, 4,902,064 and 5,538,313, each disclosure of which is incorporated herein by reference. In general terms, the CONESTOGA® tarping system 10 is configured to be mounted onto the flatbed 12 of a hauling vehicle T, as shown in FIGS. 2–3. The tarping system 10 includes a flexible cover or tarpaulin 14 with a top panel 15 and opposite side panels 16 configured to cover the flatbed 12. A series of bows 18 support the top panel 15 of the tarp and provide means for integrating the tarping system with the vehicle flatbed. A front bulkhead 20 closes the front end of the trailer, while a retractable flap 21 may be provided to close the back end of the load bed.
The tarping system 10 is configured to be retracted or compressed into a short space, such as the tarping system 10′ depicted in FIG. 2. The tarping system includes a front bow arrangement 22′ and a rear bow arrangement 24′ that sandwich the tarp 14′ therebetween, folded like an accordion. The tarping system may be extended so that the tarp 14″ spans the entire flatbed 12. In this extended position, the front bow arrangement 22′ is connected to the front bulkhead 20, while the rear bow arrangement 24″ is locked to the rear of the flatbed.
One configuration of the tarp support structure is shown in FIG. 3. The structure includes a series of bows 18 that support the tarp 14 between the front and rear bow arrangements 22, 24, respectively. The bows are connected to a carriage assembly 32 that is configured to ride within guide rails 30 attached to the opposite sides of the flatbed 12. With this arrangement, the load surface 13 of the flatbed 12 is not interrupted by the tarping system itself, thereby maximizing the load space on the flatbed.
The tarp support structure may also include uplift bow assemblies 19 that are situated between successive U-shaped bows 18. These uplift bow assemblies help maintain the tarp in tension when the cover system 10 is in its extended load-covering position shown in FIG. 1. The tarp support structure is configured so that the bows 18 and 19 can collapse onto each other when the cover system is retracted to the configuration 10′ shown in FIG. 2. The front bow arrangement 22 is connected or locked to the bulkhead 20 by a front locking mechanism 26. The front locking mechanism allows the front end of the cover system to be disengaged and the tarp 14 retracted toward the rear of the trailer, rather than to the front of the trailer as depicted in FIG. 2. The rear bow arrangement 24 includes a rear tensioning and locking mechanism 28 that pulls the tarp 14 into tension when the system is extended and locks the rear bow arrangement to the rear of the trailer 12. Details of the tarp support structure, the locking and tensioning mechanisms, and other components of the tarping system 10 may be obtained from the '484, '064 and '313 identified above and incorporated herein by reference.
The retractable tarping system 10 is adapted to be mounted on an existing trailer, such as trailer 12, without substantial modification to the trailer. In order to support the tarp supporting bows, guide rails 30 are mounted to the sides of the flatbed. While that part of the installation is relatively easy, the construction of the remainder of the cover system 10 is often very involved. The construction and installation of the cover system 10 is not conducive to being performed by the ultimate customer. Typically, installation of a retractable tarping system on a customer's flatbed occurs at pre-determined installation sites. Accuracy of the installation is important to the proper functioning of the tarping system, so complete system installation is usually reserved to trained technicians.
However, in many instances, the customer is not able to part with a trailer for an extended period of time for the installation of a cover system. Moreover, approved installation sites are frequently swamped by demand, where several tarping systems are to be installed, such as when a customer is converting a fleet of trailers to a retractable tarping system. In this instance, the often lengthy installation time for a single cover system 10 can frustrate the desire for rapid turnaround so the flatbed fleet can return to work.
Consequently, there is a need for a shipping method that allows for pre-assembly of at least a significant portion of a retractable cover system. With this novel method, the bulk of the complicated installation and assembly can occur where the system components are manufactured. Moreover, this method eliminates, or at least significantly reduces, the number of trained installation technicians that must be available off-site from the manufacturing facility.